- Orange County Sanitation District (OCSD)
- Project of Merit
- Additional Files
Project description in seveal catagories
Project aerial with descriptions
project element photos
Paper on phase 1 of of the project (steel pipe). This does not include pahse 2 (RCP).
- Additional Information
Please see attached.
Ocean Outfall Land Section and Ocean Outfall Booster Pump Station (OOBS) Piping Rehabilitation Project
- Project Location:
22212 Brookhurst St Huntington Beach, CA 92646
- Project Description:
OCSD (District) is implementing Project No. J-112, Ocean Outfall Land Section and Ocean Outfall Booster Pump Station Piping Rehabilitation Project (Project), which consists of inspection, condition assessment, and rehabilitation of corrosion damaged facilities of the land section of the outfall system at Plant No. 2 in Huntington Beach, California. The Project encompasses the rehabilitation following major facilities (Refer to the appendix for descriptions and pictures of all ten project elements):
• Various lengths of 54-inch steel suction and discharge piping at 480 mgd Ocean Outfall Pump Station
• 85-foot tall surge tower
• Beach Junction Box (BJB)
• Approximately 1,000 feet of the 120-inch steel pipe
• Approximately 2,000 feet of 120-inch reinforced concrete pipe (RCP)
• Three steel pipe risers and various other improvements
The major outfall components were constructed in phases between the 1970s and 1990s. Although OCSD periodically performs routine maintenance on the outfall facilities, the outfall system, including the 120-inch RCP section and BJB, had never been shut down for comprehensive inspection and repairs in more than 40 years.
A state of the art inspection program geared around several advanced nondestructive examination (NDE) techniques was implemented to assess the condition of the structures. For the large diameter steel piping, a combination of state-of-the-art tools, including laser profiling, EMAT, B-scan UT, and phased array UT, were employed during an extended shutdown period when a 1,000-foot section of piping upstream of the surge tower was isolated and dewatered. EMAT proved useful for prescreening large sections of buried piping and allowed the slower, more accurate, B-Scan UT to be focused on specific corrosion damaged areas and not on the entire piping system. In addition, remote operating vehicle (ROV) inspection, mini-camera inspection, and concrete core sampling were used to determine the integrity RCP outfall section extending from the surge tower to BJB. This inspection work was conducted during a low tide and reduced flow period. Extensive hydraulic modeling was performed to define the optimum inspection and construction windows and plan for contingencies.
The results of the inspections were carefully analyzed to pinpoint the corrosion-damaged areas, determine the level of corrosion at each location, identify rehabilitation requirements, and design repair solutions. Narrowing the project to specific areas within the outfall system through application of the sophisticated condition assessment techniques made it possible for OCSD to custom tailor the design to specific areas within the piping system. Additionally, this approach helped establish a realistic construction budget and a fast track construction schedule that shortened the outage for the long outfall and the discharge period through the short outfall, thereby, minimizing the environmental impacts to sensitive habitats and the public.
To reduce the long outfall shutdown period, several innovative construction techniques were employed, including the following:
• Insertion of a highly corrosion resistant, duplex stainless steel insert in the BJB through the outfall using a pipe mobile;
• Construction of carbon fiber reinforced polymer (CFRP) structural lining systems from inside the pipe; and
• Rehabilitation of the interior of the surge tower, including blasting and coating work, using a specially-designed steel work platform that was suspended from a crane over the flow while effluent was discharging below.
Completion of the project will maintain the structural integrity and reliability of the outfall system for 50 more years, thus, affording long-term protection of water environment and public health.
- Project Justification:
The rehabilitation of corrosion-damaged areas of the OCSD’s long ocean outfall system, which has been in continuous service since the early 1960s, was performed in order to extend the life of the existing facilities and prevent potential structural failures that would cause spills into the water environment, adversely impacting local beaches and sensitive habitats for wildlife and plants located adjacent to the outfall pipe. Rehabilitation consisted of numerous construction activities, including:
• Repairing, blasting, and coating long lengths of large diameter steel and concrete piping (ranging from 36-inch to 120-inch in diameter).
• Reinforcing a Beach Junction Box (BJB) with a highly corrosion resistant, duplex stainless steel pipe sleeve (insert) system that was inserted from inside the pipe.
• Constructing a carbon fiber reinforced polymer (CFRP) structural lining systems to strengthen a portion of the 120-inch steel piping and three steel riser pipes.
• Refurbishing the interior and exterior of 26-foot diameter, 85-foot tall, concrete and steel surge tower.
• Installation of state-of-the-art ultrasonic flow metering system;
• Various other appurtenant work (See appendix for a complete list).
Critical work within the 120-inch reinforced concrete pipe (RCP) section of the main (long) outfall and inside the surge tower and BJB was performed when the main outfall was shutdown and isolated from the ocean using an innovative pipe plugging system. During the main outfall shutdown, effluent was discharged through emergency (short or standby) outfall. Construction was performed on an accelerated 24/7, 20-day schedule in order to minimize the duration of discharge through the short outfall (which discharges one mile offshore) and potential impacts to public health and the environment. Rehabilitation of the long outfall segment had to be completed within a very limited window that extended between the end of the Least Tern nesting season in late summer and start of the rainy season in the middle of October. In order to bid the project and meet the construction schedule, an intensive two-year planning and design effort was undertaken, involving completion of multiple facility inspection studies and condition assessments, full EIR, contingency plans, preliminary design reports, two complete designs, two construction bid packages, and permits from multiple agencies. Extensive regulatory agency coordination and public outreach with the stakeholders was as an important part of the planning efforts.
- Special Circumstances:
Coordination with multiple regulatory agencies and stakeholders (public, NGO’s) to implement a complex construction project within a short time frame at an environmentally sensitive area adjacent to Santa Ana River Estuary, Talbert Marsh Ecological Reserve, Least Tern Natural Preserve at Huntington Beach State Park. Successful implementation of the project required the development of close working relationship between OCSD, Black & Veatch, JF Shea Construction, and multiple subconsultants. Project has been presented at various conferences throughout the state.
- Project Attachments:
Please see attached.
- Award Citation::
Orange County Sanitation District is implementing the Ocean Outfall Land Section and Ocean Outfall Booster Pump Station Piping Rehabilitation Project, which consists of inspection, condition assessment, and rehabilitation of corrosion damaged facilities of the outfall system at Plant No. 2 in Huntington Beach, California.
- Suggested Award Summary:
The Orange County Sanitation District (OCSD) is rehabilitating the land section of its 120-inch diameter, 5-mile long, ocean outfall (Long Outfall) in order to maintain its long term performance and reliability. The work includes repairing corrosion-damaged concrete and steel pipe sections, installing a new ultrasonic flowmeter, and making other repairs. In order to implement the project, the Long Outfall will be taken out of service and the shorter (1-mile long) 120 inch/78-inch outfall (Short Outfall) will be operated. The project requires construction in a public access area near a Least Tern preserve at Huntington State Beach and across the Santa River from the residents of Newport Beach. OCSD prepared a full EIR, conducted a public hearing, consulted with numerous agencies, performed in plant disinfection studies, and conducted particle transport modeling. This project addressed regulatory and environmental challenges during project planning and execution.